Blanchfield joined the Army from Chicago, Illinois in 1967,[1] and by July 3, 1969 was serving as a Specialist Four in Company A, 4th Battalion, 503rd Infantry Regiment, 173rd Airborne Brigade. On that day, in Binh Dinh Province, Republic of Vietnam, Blanchfield smothered the blast of a hand grenade with his body, sacrificing himself to protect those around him.

MOH CITATION:

For conspicuous gallantry and intrepidity in action at the risk of his life above and beyond the call of duty. Sp4c. Blanchfield distinguished himself while serving as a rifleman in Company A on a combat patrol. The patrol surrounded a group of houses to search for suspects. During the search of 1 of the huts, a man suddenly ran out toward a nearby tree line. Sp4c. Blanchfield, who was on guard outside the hut, saw the man, shouted for him to halt, and began firing at him as the man ignored the warning and continued to run. The suspect suddenly threw a grenade toward the hut and its occupants. Although the exploding grenade severely wounded Sp4c. Blanchfield and several others, he regained his feet to continue the pursuit of the enemy. The fleeing enemy threw a second grenade which landed near Sp4c. Blanchfield and several members of his patrol. Instantly realizing the danger, he shouted a warning to his comrades. Sp4c. Blanchfield unhesitatingly and with complete disregard for his safety, threw himself on the grenade, absorbing the full and fatal impact of the explosion. By his gallant action and self-sacrifice, he was able to save the lives and prevent injury to 4 members of the patrol and several Vietnamese civilians in the immediate area.